Development of Spectral and Atomic Models for Diagnosing Energetic Particle Characteristics in Fast Ignition Experiments

Abstract

This Final Report summarizes work performed under DOE STTR Phase II Grant No. DE-FG02-05ER86258 during the project period from August 2006 to August 2009. The project, “Development of Spectral and Atomic Models for Diagnosing Energetic Particle Characteristics in Fast Ignition Experiments,” was led by Prism Computational Sciences (Madison, WI), and involved collaboration with subcontractors University of Nevada-Reno and Voss Scientific (Albuquerque, NM). In this project, we have:  Developed and implemented a multi-dimensional, multi-frequency radiation transport model in the LSP hybrid fluid-PIC (particle-in-cell) code [1,2].  Updated the LSP code to support the use of accurate equation-of-state (EOS) tables generated by Prism’s PROPACEOS [3] code to compute more accurate temperatures in high energy density physics (HEDP) plasmas.  Updated LSP to support the use of Prism’s multi-frequency opacity tables.  Generated equation of state and opacity data for LSP simulations for several materials being used in plasma jet experimental studies.  Developed and implemented parallel processing techniques for the radiation physics algorithms in LSP.  Benchmarked the new radiation transport and radiation physics algorithms in LSP and compared simulation results with analytic solutions and results from numerical radiation-hydrodynamics calculations.  Performed simulations using Prism radiation physics codes to address issues related to radiative cooling and ionization dynamics in plasma jet experiments.  Performed simulations to study the effects of radiation transport and radiation losses due to electrode contaminants in plasma jet experiments.  Updated the LSP code to generate output using NetCDF to provide a better, more flexible interface to SPECT3D [4] in order to post-process LSP output.  Updated the SPECT3D code to better support the post-processing of large-scale 2-D and 3-D datasets generated by simulation codes such as LSP.  Updated atomic physics modeling to provide for more comprehensive and accurate atomic databases that feed into the radiation physics modeling (spectral simulations and opacity tables).  Developed polarization spectroscopy modeling techniques suitable for diagnosing energetic particle characteristics in HEDP experiments. A description of these items is provided in this report. The above efforts lay the groundwork for utilizing the LSP and SPECT3D codes in providing simulation support for DOE-sponsored HEDP experiments, such as plasma jet and fast ignition physics experiments. We believe that taken together, the LSP and SPECT3D codes have unique capabilities for advancing our understanding of the physics of these HEDP plasmas. Based on conversations early in this project with our DOE program manager, Dr. Francis Thio, our efforts emphasized developing radiation physics and atomic modeling capabilities that can be utilized in the LSP PIC code, and performing radiation physics studies for plasma jets. A relatively minor component focused on the development of methods to diagnose energetic particle characteristics in short-pulse laser experiments related to fast ignition physics. The period of performance for the grant was extended by one year to August 2009 with a one-year no-cost extension, at the request of subcontractor University of Nevada-Reno.